The present invention relates to a method and a device for automatic confirmation of the state of tightness of fastenings of railroad tracks, whereby from a train that is traveling over a track, it is possible to pick up a signal from each of the fastenings that indicates if the degree of tightness of the fastenings is appropriate or if, to the contrary, the degree of tightness of a particular fastening is not appropriate because it is either slack or damaged.
The upkeep costs of railroad tracks increase with the density of traffic, speed, axle load, and decrease in the weight of the rail. The traffic density is the main cause of deterioration of the tracks, by acting through the vertical and lateral dynamic total loads that the dense traffic transmits; these are transformed into fatigue and wear of the different devices or elements that form part of the fastenings of the tracks, as well as in the degradation of their geometry. This degradation will redound therefore, in the quality and in the safety of the track (defined by the standard deviations in the level, alignment, gage, etc.), the speed of the trains, and the maximum loads per axle.
Conventionally, to check and verify the state of fastening of the railroad tracks, operations are performed manually or by means of machinery in situ (that is, operative devices or mechanisms that are displaced periodically along the tracks) that include: a) reviewing, among other aspects, the tightness of the screws that cooperate in the fastening devices of these tracks, b) taking readings of torque, load or torsion, and c) proceeding to tighten those that are considered deficient.
In a railroad plant, it is known to use insulating plates for the resilient fastening of rails on crossties. Some of these plates are described in the following references: Spanish patent ES 2 115 427 relates to an insulating plate of resilient sheet type and Spanish patent ES 2 160 529 relates to an elbowed type with clip. Other known elements participating in the railroad plant include an anchoring sleeve like that described in the Spanish patent ES 2 125 603, or a resilient sole plate for railroad track such as that described in the Spanish patent ES 2 156 564. A known railroad installation is that shown in FIG. 1 of the above-mentioned ES 2 115 427 patent for an insulating plate of a resilient sheet type.